Events at Physics
Events on Tuesday, March 10th, 2015
- Chaos & Complex Systems Seminar
- Characterizing variations in Wisconsin’s extreme weather
- Time: 12:05 pm
- Place: 4274 Chamberlin Hall (Refreshments will be served)
- Speaker: Steve Vavrus, UW Department of Atmospheric and Oceanic Sciences
- Abstract: Anecdotal evidence suggests an increasing occurrence of extreme weather in recent years, but a major impediment to identifying and quantifying trends is the absence of a common measuring stick. Many definitions of extreme weather exist, but they are often haphazard and not comparable to one other for quantifying the aggregate behavior of extremes. To help remedy this problem, I created a simple, non-parametric index of extreme weather based on the combined percentile rankings of temperature and precipitation (at monthly or longer timescales). This integrated index reveals that extreme weather has indeed been unusually pronounced in recent years in Madison and across Wisconsin. However, the reasons for the high index values vary considerably by location. The temporal and spatial variations of extreme weather in Wisconsin and elsewhere are probably a combination of chaotic weather processes and emerging anthropogenic climate change.
- Host: Clint Sprott
- Theory Seminar (High Energy/Cosmology)
- Spontaneously broken supersymmetries in string compactifications
- Time: 4:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Hagen Triendl, CERN
- Abstract: Supersymmetric compactifications of string and M-theory have been intensely studied over the last years. One of the major questions in this context is the appearance of perturbative and non-perturbative string corrections. In this talk I will explain that many of these compactifications admit additional, spontaneously broken supercharges that can explain the vanishing of certain perturbative string corrections and lead to conjectures for the vanishing of certain non-perturbative corrections. I will give concrete examples and show how they are related by dualities.
- Host: Ran Lu